The mayor of Hoboken, N.J., Dawn Zimmer, said she met Sunday with federal prosecutors who are investigating her allegation that New Jersey Lt. Gov. Kim Guadagno threatened to withhold federal funds that could have helped her city recover from Superstorm Sandy.

Zimmer said she met with the lawyers from the U.S. attorney's office in Newark, N.J., and gave them diary entries and other documents that supported her allegations. In an interview after the meeting, Zimmer repeated her assertion that Guadagno told her in May that for the city to receive federal aid controlled by the state, she had to support a real-estate project in Hoboken that was important to Gov. Chris Christie.

"They came and they made a direct threat," Zimmer said, referring to Guadagno and another state official. She said she believed that Hoboken would have received much more of the post-storm aid state that officials handed out if she had done as she had been told and switched to supporting the development project.

The U.S. attorney for New Jersey, Paul Fishman, had already begun a review of allegations that associates of Christie sought to punish the mayor of Fort Lee, N.J., in September by ordering the closing of lanes of traffic leading from his borough to the George Washington Bridge. Rebekah Carmichael, a spokeswoman for Fishman, declined to comment on Zimmer's assertions.

The explosive new allegations, which the mayor first made on MSNBC on Saturday, spurred furious rebuttals from state officials Sunday.

They argued that Hoboken had not been shortchanged on federal aid to help it recover from the widespread flooding it suffered after Superstorm Sandy struck in October 2012.

"Hoboken has in no way trailed similarly situated communities in the receipt of rebuilding funds," the governor's office said in a statement.

But Zimmer continued Sunday to contend that relief money her city deserved had been held hostage by state officials. She said Guadagno took her aside in a Hoboken parking lot in May and told her the aid was tied to her support of the development project, but that she would deny she ever said so.

Zimmer said she came forward with the allegations eight months later because the scandal that erupted over the punitive traffic jams in nearby Fort Lee spurred her to talk.

"I probably should have come forward in May when this happened," Zimmer said. But she said she feared Hoboken would not get its fair share of future aid for rebuilding and fortifying against storms.